


Musical Liaisons

by bluecrownedmotmot



Category: Undertale (Video Game)
Genre: Anal, Boss/Employee Relationship, Casual Sex, M/M, Rimming
Language: English
Status: Completed
Published: 2016-06-13
Updated: 2016-06-13
Packaged: 2018-07-14 13:51:42
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,133
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7174391
Author URL: https://archiveofourown.org/users/bluecrownedmotmot/pseuds/bluecrownedmotmot
Summary: <blockquote class="userstuff">
              <p>Post pacifist ending. Burgerpants and Mettaton find themselves up late in an empty theatre.</p>
            </blockquote>





	Musical Liaisons

Burgerpants glanced at his phone and was disheartened to see that not only did it feel like it was 2:11 AM, it actually _was_ 2:11 AM. _Ugh._ He left the stack of fan letters he had just finished screening on a side table in Mettaton's dressing room so that his boss could read through at his leisure. As Burgerpants was locking the door with his key, he heard the grand piano from the stage.

He had assumed that he was the only one in the theatre, but apparently that was not the case.

Burgerpants tentatively peeked through the stage's main curtain.

The house was dark, but Mettaton had turned on lights illuminating the piano pushed far stage right. He was playing something with his right hand and leaning his left elbow on the top of the piano, fingers in his hair. He paused to write in the manuscript book in front of him. The robot changed positions restlessly, hugging his left knee, resting his heel on the bench and his chin on his knee. His right leg remained down so he could use the sustain pedal. He resumed playing.

 

Burgerpants considered going home, but after some deliberation, he emerged from backstage. He padded through the dark, heading downstage, to sneak up behind his boss.

Mettaton's curved back was to him.

“Why are you still here?”

The robot lifted his neck with alarm and his hand froze over the keys. When he recognized the voice, he relaxed without turning, slumping back down on his leg again.

“I could ask you the same question, darling.”

“I started late today. It's more peaceful when I don't have to listen to your rehearsals,” replied Burgerpants.

“Believe me, if _I_ didn't have to be there myself, I wouldn't,” said Mettaton dryly. Preparing for a new show was not Mettaton's favorite activity. He could deal with the tribulations of performing and touring. The moments on stage, before an excited audience, made everything worth it. Rehearsing for an extended stretch of time was a necessary evil, trying his patience and the sanity of everyone who had to interact with the demanding robotic frontman.

“What are you working on?” Burgerpants asked.

“Mmm, just putting things in my head down on paper,” Mettaton sighed.

“Sounded nice. I mean, better than that album you did about how terrible I am at my job.”

Mettaton glanced back at Burgerpants with a guilty smile. “I think your work ethic has improved a little since then.”

“Not having to do food service helps. I mean, wow, going through the crap people send you is really where it's at.”

“And when I said a little, I really meant a little.”

Mettaton put his left leg back on the ground, straightened up, and played something cheerful with both hands.

“Didn't know you could actually play.”

“Can't really well, darling. I taught myself. I can only do just enough to write and mess around.”

 

When Mettaton was done improvising, he looked over at Burgerpants again, with curiosity.

“You've had plenty of opportunities to slink away, and yet you're still here, my dear. I'm guessing you don't have any hot dates tonight? Is it robooty-call o'clock?”

“It's not like that,” said Burgerpants defensively, straightening his tail. “I just wanted to see how you were, that's all.”

“Oh,” said Mettaton lightly, striking a diminished seventh and letting it hang in the air. He seemed almost disappointed. “Well, I'm fine.”

Burgerpants was frequently completely thrown off by his boss. Right now was no exception. He wasn't entirely sure he wanted to do this at the moment. He had started to believe that his boss was not actually out to get him, but the fact remained that Mettaton intimidated the shit out of him. But there had been that other time...

“...Unless you want it to be like that?” began Burgerpants sheepishly.

Mettaton perked back up. He resolved the lingering chord. “We're the only ones here, right?”

“Uh. Yes?”

“Oh _splendid_. I need something from my dressing room. Stay here, darling.” The robot stood up from the bench and trotted off into the wings.

 _What am I getting into_ , wondered Burgerpants, feeling ridiculous. He sat down on the edge of the circles of light.

 

Mettaton returned with his bag.

“Where are we going?” asked Burgerpants.

“Nowhere. We're going right here. Just figured you might need this.” He reached into his bag and tossed a bottle of lube to Burgerpants. Of course, Burgerpants fumbled while catching it. Mettaton snickered. The robot sat on the piano bench facing his flustered employee. He crossed his legs.

“Now. Touch yourself, and we'll work from there,” Mettaton ordered, with directorial authority.

“Why did I agree to this,” lamented Burgerpants.

“I'm way older than you, my child. That means you trust my judgment and do as I say.”

“You're a fucking robot,” Burgerpants scoffed. “You're like, what, a few years old at most?”

Mettaton shrugged mysteriously. “Take my word for it. I'm older than you. Give me a good show.”

 

Burgerpants looked out into the dark house and reluctantly stimulated himself through his pants.

“This is unsexy.”

“For you, maybe,” replied Mettaton.

“Yeah, but you get off on embarrassing me.”

“You're on to something, sweetheart. Lemme see your dick.”

“Could you shut up?”

“Never. Now, obey me and we'll move things along.”

Burgerpants pulled off his pants and underwear, getting it over with. “I can't look at you,” he mumbled.

“You're not looking at me anyway,” Mettaton laughed.

“But I can tell you're there,” Burgerpants whined.

“Do I scare you?” Mettaton purred. “Do you have stage fright? That's fucking adorable. Pretend I'm not here.”

Burgerpants sighed, closed his eyes, and touched himself.

 

Mettaton watched his employee curiously. He liked that Burgerpants was nervous and ashamed. The emotions were irresistible. After a moment, Mettaton delicately traced the heart on his stomach, touched between his legs. Burgerpants was just so much fun to play with. He had to take care not to push him too far, but he felt powerful holding that responsibility. His soul pulsed with sadistic, voyeuristic joy. This was going to be fetish fuel for months.

Mettaton didn't want to get caught with his hands where they were and he certainly was not going to risk more directly touching himself, not right now. He wanted to control this.

 

Meanwhile, Burgerpants imagined strangling his boss. He came up the idea because it seemed like a great way to get Mettaton to stop talking, but the image was also appealing for other reasons. He vividly saw Mettaton's terrified facial expressions in his mind's eye and he was suddenly rock hard as he jerked himself off.

“Thinking of me?” teased Mettaton, making an effort to sound normal, to sound like certain parts of him were not were throbbing.

“Believe it or not, yes,” admitted Burgerpants.

“ _Really_ ,” mused Mettaton, his voice coming out a bit more breathy and helpless than he had intended.

Burgerpants opened his eyes.

 _Shit_. Mettaton's hands were suspiciously placed, but he'd stopped moving them just an instant before his employee looked at him.

Burgerpants suspected that Mettaton had not exactly been disinterestedly watching him.

“What?” asked Mettaton smoothly.

Burgerpants just shook his head.

 

Mettaton licked his lips and got to his feet. He dived over to touch his toes, stretching his legs. Then he strode to the side of the piano. The top was closed and he leaned his upper body over on it. He raked one hand into his hair, ran the other down his body to rest on his rump, and looked back at Burgerpants.

“Now that you're up for it, I think you need somewhere to put that, kitten. Do you think we could go at it like this?”

Burgerpants was fairly tall, so it wasn't out of the question. He got up, jumping at the opportunity to no longer be the center of attention.

“Probably, sir.” Burgerpants lubed up. Mettaton pulled his latex pants down.

Burgerpants tentatively touched Mettaton's bare silicone butt. It was a good butt.

“As your boss, I suggest you ram your cock into me,” said Mettaton conversationally.

“Calm yourself,” said Burgerpants, “I will.”

He rubbed the side of his face against the robot's glorious rear end. _Fuck it._ He ran his tongue down Mettaton's crack. He buried his face in the robot's butt and rimmed him.

“Ohhh... I knew hiring you was a very, very good idea,” Mettaton giggled.

Burgerpants extricated himself from the prodigious amount of shapely, synthetic booty for a moment. “Do I even want to know why you hired me in the first place?” he wondered, before pressing his tongue back into the tight folds of Mettaton's pucker.

“I assure you I didn't have this in mind. I just found you amusing, that's all. Now here you are. Eating my asshole. My, my, Burgerpants. I didn't realize you were such a freak. It turns me on. It really does.”

Burgerpants fingered Mettaton's robo-anus ( _or whatever_ , thought Burgerpants deliriously) with a slick finger. Mettaton allowed it.

 _What kind of sick pervert builds a robot like this_ , wondered Burgerpants, his heart beating fast.

“Spread your legs. You're still a little too tall. ”

“With pleasure.” Mettaton slid his heels apart.

 

Burgerpants pushed into the robot. Mettaton groaned and bit the tips of his gloved fingers. Burgerpants rested his palms on the piano on either side of his boss. He slowly moved in and out.

“Goddamn,” he panted. He leaned his temple against Mettaton's shoulder.

“Relax. Take your time,” advised Mettaton.

Burgerpants took his weight off the piano to grasp Mettaton's hips.

Mettaton sighed contently as his employee plowed him. He arched his back, tilted his head sideways to look back and watch Burgerpants for a while. Then he laid the side of his face down on the piano in front of him. His hair contrasted like glossy accidental keys against the gleaming white piano.

Burgerpants reached a hand around to Mettaton's groin, but Mettaton quickly centered the heel of his left boot precisely where the bone in Burgerpants' left foot was closest to skin and put just enough weight down to serve as a warning.

“Don't touch me,” Mettaton hissed.

“Ow, what is your _problem_?”

“You do what I tell you, when I tell you, and you don't do anything else except enjoy yourself,” responded Mettaton silkily. “That's the way it is.”

“What if I want to do something for you?”

“That's not what I want.”

“That's not fair.”

“Life's not fair,” Mettaton snapped. “Stop screwing your boss and go hit on your blue bunny friend if you want a relationship.”

That shut Burgerpants right up.

 

Mettaton wriggled away from Burgerpants. He hadn't bothered to take his pants off, so he took just a few tiny steps before sinking to his knees on the stage floor.

“Get down here. Fuck me like this.” He laid his chest on the ground, kept his butt in the air.

“Fine.” Burgerpants knelt down and slid back into Mettaton. He had to admit, he liked the way this position felt. A lot. He slowly crept his fingers back around Mettaton's hips and thrust into him.

“It drives me wild when you do exactly what I say,” growled Mettaton.

“Yeah, I've noticed.”

“Come inside me.”

“Are you sure you don't want anything?”

“Mmmm,” Mettaton considered. “You could... Pull my hair. When you come. That's all I want.”

“Really?”

“Yeah.”

Burgerpants closed his eyes. He ran a claw up the back of Mettaton's neck and wrapped locks of soft hair around his fingers. He fucked Mettaton furiously.

Mettaton mumbled blissful nonsense and slid flat out on the stage, keeping his hips pushed up. He used his hands to part his cheeks so that his employee could plunge the entire length into him. Burgerpants, deep inside his boss, couldn't take it anymore. He cried out as he came and lifted Mettaton's head back by tightening his fingers against the roots of the robot's hair, pulling hard. Mettaton grimaced and whined softly.

 

Burgerpants caught his breath and let Mettaton's head down to the floor gingerly. He pulled out, retrieved his pants and put them back on. Mettaton remained stretched out prone on the floor. He ached, but he'd take care of it later when he was alone. Burgerpants laid down on his back beside the robot.

“Why the hell do you come on to me anyway?” asked Burgerpants.

Mettaton looked somewhat disheveled and tired. His head was turned with his cheek pressed against the stage.

“You're cute. And available. You're a little high strung and lacking in sense of humor... But you're a good kid.”

Burgerpants thought about this. Mettaton was a weird dude. But he had a more pressing concern on his mind.

“So... Do you think that bunny is into me?”

Mettaton smiled. “Possibly.”

**Author's Note:**

> Edit 13 June 2016 - There's an illustration for this. If you'd like to see it, go here: http://motmotfluttersforth.tumblr.com/post/145840747629/musical-liaisons-by-bluecrownedmotmot
> 
> Enjoy,  
> Motmot


End file.
